Plastic cover for dispensing container



J. A. FOSTER PLASTIC COVER FOR DISPENSING CONTAINER Feb. 27, 1968 4Sheets-Sheet 1 Filed Sept. 6, 1966 w M. a i 5 H0 W m m m 5 l a 22 w 3 Wm 4 0 //r 9 cyqw-Tonuosvf Feb. 27, 1968 J. A. FOSTER PLASTIC COVER FORDISPENSING CONTAINER 4 Sheets-Sheet 2 Filed Sept. 6, 1966 29 rovamw-odam cAFwzaz yg JJJJ Cflflomosyf Feb. 27, 1968 .1. A. FOSTER PLASTICCOVER FOR DISPENSING CONTAINER 4 Sheets-Sheet Filed Sept. 6, 1966 Feb.27, 1968 J. A. FOSTER PLASTIC COVER FOR DISPENSING CONTAINER 4Sheets-Sheet 4 Filed Sept. 6, 1966 24 1 fiMW CBTTcrQIQEYJ United StatesPatent O 3,370,757 PLASTIC CDVER FOR DISPENSING CONTAINER John A.Foster, Rockford, Ill., assignor to J. L. Clark Manufacturing Co.,Rockford, III., a corporation of Illinois Continuation-impart ofapplication Ser. No. 447,466, Apr. 12, 1965. This application Sept. 6,1966, Ser. No. 586,903

Claims. (Cl. 222-153) ABSTRACT OF THE DISCLOSURE A generally rectangularsingle piece container cover is molded of resilient plastic and formedwith an oblong central flap joined at one end by an integral hinge toone end of a dispensing opening in aflat top plate. Around the remainingperipheral edge, the flap is joined integrally to the top plate by a webof no substantial width and sufliciently thin to break and be torn allthe way to the hinge ends by an upward pull manually applied to the freeend of the flap to swing the latter upwardly and uncover the plateopening. By virtue of the resiliency of the plastic, no permanentdeformation of the plastic occurs during breaking or tearing of the webso that the flap telescopes back into the torn edge of the plate openingand fits closely therein to provide tight rescaling. An overhangmgflange around the flap and underside ribbing of the tlap and plateprovide the rigidity for limiting the reclosing movement while providinguniform plastic cross-sectrons to permit of high production molding.

This application is a continuation in-part of my prior applicationSerial No. 447,466, filed April 12, 1965, now abandoned.

This invention relates to dispensing containers and particularly to amolded plastic cover therefor providing a hinged closure for an openingthrough which the contamer contents may be removed or dispensed.

The primary object is to provide a plastic container cover of the abovecharacter and novel construction which is molded in a single piece withthe closure integrally joined to the cover by a molded hinge across oneedge and around the remaining periphery by a molded tear web adapted tobe torn easily by an upward swinging of the closure out of its moldedposition to elfect the initial uncovering of a dispensing opening, theclosure being left hinged to the cover and adapted for repeated tightreclosure and reopening.

A further object is to provide a tear web of the above character whichadapts the closure for tight reclosure along the torn edges simply byswinging the closure to or beyond its initial molded position.

Another object is to control the extent of the reclosing movement in anovel manner so as to insure relatively fight sealing of the dispensingopening.

Still another object is to achieve a snap-like action in the reclosingof the closure.

The invention also resides in the novel construction of the couplingbetween the hinged closure and its support to facilitate the initialtearing of the closure seal by a manually exerted pulling force.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which FIGURE 1 is a perspective view of adispensing container having a cover embodying the novel features of thepresent invention.

FIG. 2 is a four times actual size section taken along the line 2 2 ofFIG. 1.

' 1 ing to tightly reclose the opening.

3,370,757 Patented Feb. 27, 1968 'FIG. 2a is an enlargement of a part ofFIG. 2.

FIG. 3 is a section taken along the line 33 of FIG. 1.

FIG. 4 is a bottom view.

FIG. 5 is a perspective view of the improved cover after opening theclosure.

FIG. 6 is a section taken on the line 6-6 of FIG. 1 with the closurepartially open.

FIGS. 7, 8 and 9 are sections taken along the line 77 of FIG. 6 butshowing dilierent conditions of partial opening and reclosure.

FIG. 10 is a perspective view similar to FIG. 1 showing a modification.

FIGS. 11 and 12 are fragmentary sections taken respectively along thelines 11-11 and 1212 of FIGS. 10 and 11. 7

'FIG. 13 is a fragmentary perspective view of a part of FIG. 10 with theclosure open.

FIG. 14 is a section taken along the line 14-14 of FIG. 11.

FIG. 15 is an enlarged view of part of FIG. 9.

FIG. 16 is a view like FIG. 4 showing a modified and preferredconstruction of the cover bottom.

FIGS. l7, l8 and 19 are sections taken respectively along the lines17-17, 18-18 and 1919 of FIG. 16.

While the .invention is shown for purposes of illustration incorporatedin a cover 10 for a conventional conta'iner for spices, food flakes andthe like having a metal body 11 of generally rectangular cross-sectionand rounded corners, it will be understood that the cover may takevarious other shapes and be secured in various ways to other kinds ofdispensing containers.

The cover is composed of resilient plastic and comprises a generallyflat top plate 12 defining a dispensing opening 13 (FIG. 5) closed by arelatively fiat flap 14 hinged at 15 on the plate across one end of theopening for swinging between closed and open positions (FIGS. 1 and 5).The hinge is formed by a relatively thin web or membrane integrallyjoining the plate 12 with one end of the flap 14 which is elongated inthe preferred form shown in FIGS. 1 to 9 to correspond to the desiredsize and shape of the dispensing opening.

Herein, the cover is coupled to the end of the body 11 by interlocking ahead 16 on a skirt 17 depending from the periphery of the plate with thedownwardly facing edge 18 of a hem 19 at the end of the body. The skirtcoacts with a second and shorter skirt 21 to form a groove in which thelip 22 of the body is wedged to form an airtight seal all around thecover.

The plate 12, the skirts 17 and 21, the closure flap 14, and the hinge15 are all formed in a single molding operation using a relativelyresilient thermoplastic material. One suitable material is ordinarypolyethylene, such for example as that sold by Du Pont under the tradename Alathon-ZO.

-In accordance with the present invention, the closure flap is molded inthe closed position (-FIGS. 1, 2 and 3) and, around the free end andsides all the way to the ends of the hinge 15, is integrally joined inthe molding operation to the edge 20 of the top plate 12 defining theopening 13 by a tear web or membrane 23 which has no substantial widthand is of sufiicient thinness to be torn and broken by an upwardlydirected pull manually applied =while gripping a tab 24 Which may beattached to the flap near the free end thereof. Thus, the tear Webcoacting with the hinge 15 completely closes the dispensing opening 13between the ends of the hinge 15 while allowing the flap to be releasedautomatically in the lifting of the flap to effect the initial openingof the container. There after the flap remains attached to the cover'bythe hinge and thus is swingable reversely and guided into the open-While the tab may be integral with the top of the flap and projectupwardly therefrom'while being pulled upwardly, it is formed in thepresent instance as an integral extension of the free end of the flapand lies substantially in the plane thereof. To facilitate gripping ofthe pull tab-24, a series of shallow parallel ribs 25 are molded on itstop and bottom surfaces. The tab terminates near one edge of thecoverand is spaced a short distance above the top of the plate 12 toafford easy access to the users thumb in the initial gripping of the tabwhile enabling the tab in its molded position to be disposedsubstantially in the plane of the closure flap. In the preferred form,such spacing is achieved by recessing the top of the plate below the taband at the edge of the plate as indicated at' 26. The tab is relativelythin and easily bent or swung upwardly to allow for firm finger grippingover relatively large areas. For the same reason, the tab is ofsubstantial length as permitted by spacing the narrow end of thedispensing opening 13 a substantial distance from the end of the cover.

The hinge 15 is disposed close to and extends across the opposite end ofthe cover and comprises a narrow web formed in the present instance bygrooving the under side of the cover as indicated at 27 (FIGS. 3 and 4)and across the full width of the closure flap at the wide end thereof.Preferably and at spaced points 27 along its length, as shown in FIGS.18 and 19, the hinge is thickened somewhat to provide in the moldpassages large enough in cross-section to allow the molten plastic toflow through freely and to the remote parts of the mold cavity. Thereadily flexible web thus formed in the initial molding is integrallyjoined to the end of the flap, locates the hinge axis close to the sideend of the dispensing opening and permanently closes this end of theopening.

To enable the tear web 23 to be broken and torn easily by a force of themagnitude that can be exerted bymanually gripping and pulling upwardlyon the tab 24, the portions thereof along opposite sides of the flap 14-preferably converge longitudinally of the flap toward each other firstgradually as indicated at 23 (FIG. 4), beginning at the ends of thehinge 15, then more sharply near the free end portion of the flap asindicated at '23 and finally merge with each other at a narrow butsomewhat rounded apex 23. Thus, in the initial upward pulling of thetab, the entire force is applied to a very short length of the tear webat this apex and this is easily stretched edgewise and then broken underthe force capable of being exerted manually. After this initial break,rupture of the remainder of the web occurs with a true tearing actionand progresses along the side portions 23* and 23 of the web under asomewhat lesser pulling force. Such tearing is continued allthe way tothe ends of the hinge in order to effect full uncovering of-the opening13, the flap remaining joined to the cover only by the hinge web 15.

The'tear web 23 and the closure flap and top plate edges joined therebyare dimensioned and shaped in a novel way to facilitate the initialopening by a true tearing action along well defined lines, permit lowcost molding using modern high production techniques, and leave theopposed edge surfaces of the flap and plate conditioned after tearingfor easy and tight reclosure of the a dispensing opening. For thispurpose, the flap and the surrounding portions of the plate 12 areconstructed to possess substantial rigidity and the web is joined to thefiap around an outwardly facing upright surface or Wall 30 which extendsaround the periphery of the flap between the ends of the hinge and is ofsubstantial vertical width greater than the thickness of the surroundingedge portion. 20 of the top plate 12. While the periphery of the flap.may take various cross-sectional shapes to provide this wall, thelatter, in the present instance, is the outer upright face. of aperipheral rib or shallow skirt 28 which, in. order to enable the top ofthe flap to be left smooth and of attractive contour, is formed aroundthe under side of the flap, depends from the outer edge thereof andprojects somewhat below the tear web and the top surface of the plate.The rib is sized and shaped to telescope closely within the dispensingopening 13 upon reclosure of the flap after the initial tearing andopening of the latter, the rib tapering downwardly somewhat and beingbeveled along its lower edge to guide its entry into the dispensingopening as the flap, after tearing away from the top 12, is swungreversely into the. plane of the opening. 7

To insure proper tearing while minlmizinz the irregularity of. theresulting torn edges, the web 23 is made as narrow as possible to avoidstretching and insure smooth tearing and thin enough to insure easy'tearing while permitting uniformity in high speed molding and insuringcontinuity around the full periphery of the closure flap. Thus, in thepresent instance, the web is only a few thousandths, for example, 0.005of an inch wide and about 0.005 of an inch thick as indicated in FIG.2a. Minimum thickness at the apex 23 is desirable to insure easybreaking to start the tearing action by upward pulling of the tab 24. V

The inner edge of the web 23 is integral with the rib surface or wall 30and the outer edge is integral with the defining edge 20 of thedispensing opening 13 and sub stantially in theplane of the top surfaceof this plate. Formation of such a web with tools capable ofwithstanding long service use is facilitated by inclining, as indicatedat 29 (FIG. 3), the bottom surface of the plate 12 around the edge 2%)of the dispensing opening, the web being formed in the molding operationby virtue of the, slight spacing of the ribsurface 30 inwardly from the.substantial intersection of this inclined surface 29 and the top of theplate 12. Thus, the web, althoughpof no substantial width and so thinthat it may be broken and torn easily, may be formed accurately and uniformly in high speed plastic molding operations.

By spacing; the web 23 somewhat aboveand beveling the lower edge of therib 28, the latter coacts Withthd' edge 20 of the dispensing opening toguide the flap into this opening as it is swung downwardly to reclosethe opening. Thev rib thus becomes telescoped closely with the edge ofthe opening. thus producing a tight seal-all around the latter as morefully described later.

The desired overall rigidity of. the closure flap. is achievedby the rib28 and. a plurality of cross-ribs 31 and a crossing longitudinal rib 32on the under side of the flap with the tops and ends of these. ribsmolded integral with the flap and the rib 28. The area of the top plate12 surrounding the dispensing opening. is made relatively rigid bymolding spaced ribs on the underside of the plate within and integralwith the peripheral skirt 16. The ribs may extend transversely andlongitudinally of the plate as indicated at. 33 in FIG. 4.

FIGS. 16, 17 and 18 show another rib arrangement which. imparts greaterand adequate rigidity to. the flap end of the cover so as to preventtheskirtfrom flexing inwardly and slipping past the hem 19 under, theupward pull applied, to the tab 24 to tear the flap. free. In this form,elongated andsubstantially straight ribs 45 disposed. close to the sidesof the opening 13 are extended along the major length of the opening,past the apex 7 thereof and to the short side of the skirt 17. Similarand shorter ribs 46 extend across the corners of. the skirt and mergewith the outer ends of the ribs 45. Short cross-ribs 47 and knock-outpins 48. are spaced along the ribs 45, 46 and join these integrally withthe long and short sides of the skirt. The truss-like structure thusformed by the ribs, the top 12 and the skirt 11 imparts the desiredrigidity to the cover while maintaining all sections of the plastic ofsubstantially uniform thickness. Thus, the cover, in spite ofthefcomplexity of its shape,

may be formed with the required accuracy and without distortion in.accordance with modern high production molding techniques.

It will be observed that the top of the closure flap 14 is somewhatwider than the dispensing opening 13 so that edge portions 34 thereofconstitute flanges which project beyond and overlie the depending skirt28 and are spaced somewhat above the top surface of the plate 12 in theinitial molded position of the latter (FIG. 2). These portions 34, whichcould take the form of lugs, are adapted to engage the cover top andlimit the downward movement of the flap during reclosure of the opening.Thus, the flap cannot under an abnormal downward pressure applied duringreclosing be bent and forced through the opening 13.

Tearing of the web 23 by pulling the flap upwardly as above describedleaves minute and slightly irregular projections 35 (FIG. 7) spacedalong the rib 28 and similar projections 36 at the edge of the opening13. These irregularities, in spite of their short length due to the welldefined lines of tearing of the web, are used to advantage in effectinga snap-like reclosure of the flap and eifective holding thereof inclosed position. Thus, with the stop flanges 34 spaced somewhat abovethe web, the flap may be depressed slightly below its original positionduring which the irregularities along the rib 28 flex and pass by theirregularities 36 on the edge 20 of the cover as illustrated in FIG. 8.Such interlocking, especially at or near the free end of the flap,eifectually holds the same closed but permits easy reopening duringwhich the irregularities 35, 36 bend reversely and pass each other asthe flap is swung upwardly.

With the flanges 34 of the closure flap spaced above the tear web 23 asabove described, the sealing pressure attainable on reclosure of theflap may be increased by providing a small downward taper, for example10 degrees as indicated at 37 (FIG. 3) all around that upright portionof the rib 28 which is disposed between the tear web 23 and the stopflanges 34. Thus, by continuing the application of downward pressure tothe flap after it reaches its original position, the tapered surface iswedged into the dispensing opening 13.

More positive snap reclosure of the flap may be achieved if desired bymolding shallow projections such as beads 38 along the outer surface 30of the rib 28 between the flanges 34 and the tear web 23. In thisposition and under sufiicient pressure applied to the free end portionof the flap in closing the latter, some parts of these projections will,due to the yieldability of the edge 20 and the rib 28, pass through theopening 13 and snap outwardly beneath the torn edge 36 as shown in FIGS.9 and 15. The flap is thus held more effectually in closed position butmay be swung upward easily when it is desired to reopen the container.

For closures which are somewhat smaller or narrower than that abovedescribed, sufliciently effective reclosure may be achieved by theinterengagement of the torn edges as explained above. Such alternativeconstructions are shown in FIGS. 10 to 14 in which the partscorresponding to those previously described are indicated by the samebut primed numbers. As initially molded, the parts are shaped as shownin FIGS. 10, 11 and 12 with an elongated closure flap 14' joined to thetop plate 12 by a hinge web 15, the peripheral edge of which is joinedintegrally to the cover by a tear web 23' which in this instance isdisposed substantially flush with the top surface of the cover at theupper edge of a rib 28. The latter extends around the sides and end ofthe flap and is formed around its exterior with a small downward taperindicated at 41.

As the projecting pull tab 24' is gripped and pulled upwardly from themolded position shown in full in FIG. 11 and to the position shown inphantom, the web 23' is first stretched and broken at the free end ofthe flap 14 and beneath the pull tab. Then, as the upward swinging iscontinued, the web is torn progressively along opposite side edges ofthe flap and to the ends of the hinge 15 the dispensing opening is thusuncovered.

To reclose the opening, the flap 14 is swung reversely and downwardly,the lower end of the rib 28' being guided into the opening. As the flapcomes into the plane of the top plate 12, the irregularities on the tornedges on the rib and plate pass by and interlock with each other justbefore the pull tab comes into contact with the top. Such a narrowclosure flap will stop in closed position (FIG. 10) under the reclosingpressure applied by the average user.

The tear web 23" may be of the same construction and similarly arrangedrelative to the closure flap 24" when the dispensing opening 13" is ofrelatively small size as shown in FIGS. 11, 13 and 14. In this instance,the outer end of the dispensing opening is of arcuate shape and thecorresponding portion of the rib 28 is deepened and formed as laterallyspaced depending teeth 42. The spaces 43 between adjacent ones of theseare sized to form openings through which the container contents may besifted after the tear web 23 has been torn and the closure flap swungupwardly to the position shown in FIG. 13 and in phantom in FIG. 11. Thelower ends of one or more of the teeth at the free end of the flap areformed with a lug 44 positioned to engage the cover at the edge of thedispensing opening thus limiting the opening movement of the flap to thesifting position.

It will be apparent from the foregoing that the easy opening of theclosure flap and the tight sealing on reclosure is attributable toseveral of the above mentioned features including the. molding of theclosure in a single piece of resilient plastic thus avoiding anypermanent deformation that would interfere with telescoping of the tornedges back together and effectual rescaling of the flap around thedispensing opening. Such effective reseaiing is also achieved by makingthe tear Web 23 without substantial width and disposing the same abovethe lower edge of the rib 28. This provides for clean and accuratetearing of the web and the elimination of torn edges that would becomerolled over and wedged between the opposed surfaces of the flap andplate and thus prevent tight reclosure. The lower beveled edge of therib 28 guides the entry of the torn flap back into the dispensingopening to achieve close telescoping resealing. By forming the rib 28around the periphery of the flap and ribbing the undersides of the plateand the flap as indicated at 46, 47 and 48, the desired uniformcrosssections of the molded piece are provided to permit of highproduction molding while maintaining the rigidity of the fiap and platerequired for enabling the overhanging flange 34 to be used to preventthe flap, during reclosure, from being pushed down through thedispensing opening.

While various forms of the term telescope have been used in thespecification and the claims to describe the interfitting action of thehinged closure flap 14 and the opening 13 upon reclosure of the cover,it is to be understood that the use of the term telescope hereincontemplates hinged telescoping of the parts rather than relative bodilymovement or bodily sliding of the parts as the term telescope denotes inits true sense.

I claim as my invention:

1. A container cover molded of a single piece of resilient plastic andcomprising an apertured top plate having an internal edge defining anopening adapted, when uncovered, for the dispensing of the containercontents therethrough, a flap covering said opening, a flexible webmolded integrally with and permanently joining one end of said flap andsaid plate edge and forming a permanent hinge across the correspondingedge of said opening, the remaining periphery of said flap being moldedwith an outwardly facing upright surface corresponding in shape to andadapted for close telescoping within the remaining peripheral length ofsaid plate edge between opposite ends of said hinge, a tear webintegrally joining said surface and said remaining plate edgecontinuously around the latter and cooperating with said hinge web tocompletely close said opening in the cover as molded, a pull tabintegral with said flap at the end opposite the hinge, said tear webhaving no substantial width and being sufliciently thin to be broken byan upwardly directed pull capable of being applied by manual gripping ofsaid tab and then to tear along opposite sides of the flap and to saidhinge ends as such pull and upward swinging of the flap is continued touncover said dispensing opening, said hinge web being thicker than saidtear web and sufiiciently strong to remain untorn during such upwardswinging, said breaking and tearing of said tear web occurring withoutpermanent deformation of said resilient plastic and leaving around saidflap surface and said opening torn edges which, by virtue of theresiliency of said lastic, remain in their originally molded shape andsufficiently flexible to interengage or pass each other as the flapafter tearing is swung reversely to or beyond its original moldedposition.

2. A container cover as defined in claim 1 in which said tear web isspaced above the lower edge of said upright flap surface and such loweredge coacts with the torn edge of the plastic around said opening toguide the entry of the torn edge of the flap back into interengagementwith the opening edge as the flap is swung back to its untorn position.

3. A container cover as defined in claim 2 in which the guiding of saidflap into the torn edge of said opening is facilitated by a bevel alongsaid lower edge of said upright flap surface.

4. A container cover as defined in claim 1 in which the width andthickness of said tear Web is on the order of a few thousandths of aninch.

5. A container cover as defined in claim 1 in which the top and bottomsurfaces of said plate defining said dispensing opening convergeinwardly to the thickness of said Web at said upright flap surface.

6. A container cover as defined in claim 1 including a short projectiondisposed above and extending outwardly from said upright side surface ofsaid flap and adapted upon reclosure of the flap to pass the torn edgeof said opening and engage beneath the latter to hold the flapreleasably in closed position.

7. A container as defined in claim 1 in which said side surface of theflap above said tear web converges downwardly and inwardly and is sizedto wedge within the torn edge of said opening as said flap is swungreversely and the torn edge of the flap is moved past the torn edge ofsaid opening and beyond its original molded position.

8. A container cover as defined in claim 1 in which said peripheral flapsurface is the external face of a rib integral with, depending from, andextending around the flap periphery between the ends of said hinge, andinclud-.

ing cross-ribs integral with and spanning said peripheral rib to impartsubstantial rigidity to the flap while maintaining substantialuniformity in all cross-sections of the latter.

9. A container cover as defined in claim 8 including a skirt extendingaround and depending from the outer periphery of said top, elongatedribs integral with and depending from said top along opposite sides ofsaid opening and integral with said skirt beyond the end of saidopening, and cross-ribs spaced along said first ribs and integrallyjoining the latter with said skirt.

10. A container cover as defined in claim lin which a rib depending fromand extending around the free end of said flap below said tear web isformed with a plurality of depending projections laterally spaced toprovidea plurality of downwardly opening recesses which cooperate withsaid top edge to define sifter holes after tearing of said web andupward swinging of said flap to expose such holes.

References Cited UNITED STATES PATENTS 2,574,720 11/1951 Trout et a1 220-27 3,083,858 4/1963 Biedenstein 220-27 3,144,180 8/ 1964 Phillipps etal 22248O 3,250,436 5/1966 Kurtz 222528 STANLEY n. TOLLBERG, PrimaryExaminer.

